'\" te
.\" Copyright (c) 2007, Sun Microsystems Inc. All Rights Reserved.
.\" Portions of this manual page are derived from documentation obtained from linuxmanpages.com
.\" The contents of this file are subject to the terms of the Common Development and Distribution License (the "License").  You may not use this file except in compliance with the License.
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.TH DIRFD 3C "Oct 24, 2007"
.SH NAME
dirfd \- get directory stream file descriptor
.SH SYNOPSIS
.LP
.nf
#include <dirent.h>

\fBint\fR \fBdirfd\fR(\fBDIR *\fR\fIdir\fR);
.fi

.SH DESCRIPTION
.sp
.LP
The \fBdirfd()\fR function returns the file descriptor associated with the
directory stream \fIdir\fR.
.sp
.LP
This file descriptor is the one used internally by the directory stream
operations. See \fBopendir\fR(3C), \fBclosedir\fR(3C), \fBreaddir\fR(3C),
\fBrewinddir\fR(3C), \fBseekdir\fR(3C), \fBtelldir\fR(3C).  The file descriptor
is automatically closed when \fBclosedir()\fR is called for the directory
stream \fIdir\fR or when one of the \fBexec\fR functions is called.  See
\fBexec\fR(2).
.sp
.LP
The file descriptor can safely be used only by functions that do not depend on
or alter the file position, such as \fBfstat\fR(2) and \fBfchdir\fR(2).
Closing the file descriptor with \fBclose\fR(2) or modifying the file position
by means other than the directory stream operations listed above causes
undefined behavior to occur when one of the directory stream operations is
subsequently called with the directory stream \fIdir\fR.
.SH RETURN VALUES
.sp
.LP
Upon successful completion, the \fBdirfd()\fR function returns an open file
descriptor for the directory associated with the directory stream \fIdir\fR.
.SH ERRORS
.sp
.LP
There are no defined error returns.  Passing an invalid directory stream as an
argument to the \fBdirfd()\fR function results in undefined behavior.
.SH USAGE
.sp
.LP
The \fBdirfd()\fR function is intended to be used to obtain a file descriptor
for use with the \fBfchdir()\fR function.
.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(7) for descriptions of the following attributes:
.sp

.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
Interface Stability	Committed
_
MT-Level	Safe
.TE

.SH SEE ALSO
.sp
.LP
.BR close (2),
.BR exec (2),
.BR fchdir (2),
.BR fstat (2),
.BR closedir (3C),
.BR opendir (3C),
.BR readdir (3C),
.BR rewinddir (3C),
.BR seekdir (3C),
.BR telldir (3C),
.BR attributes (7)
